A Glasgow smile (also known as a Chelsea smile, or a Glasgow grin, smiley, Huyton, A buck 50 or Cheshire grin) is a wound caused by making a cut from the corners of a victim's mouth up to the ears, leaving a scar in the shape of a smile. Following this incision, the victim is usually kicked in the stomach or genitals, causing them to scream and thus tearing their face apart wider. The act is usually performed with a utility knife or a piece of broken glass, leaving a scar which causes the victim to appear to be smiling broadly. 
- Fretts, Bruce (12 November 2014). "Sons of Anarchy's Tommy Flanagan on Those Facial Scars, This Final Season, and Chibs". Vulture. New York. Retrieved 12 January 2019.
- Mills, Rod (27 October 2008). "Surgeon Says Hospitals Treat a Knife Victim Every Six Hours". The Daily Express. Retrieved 20 November 2009.
- Arlidge, John (24 April 1995). "City Slicker Glasgow". The Independent. London. Retrieved 20 November 2009.
- Peter Ward Booth; Barry L. Eppley; Rainer Schmelzeisen (2003), Maxillofacial trauma and esthetic facial reconstruction, Churchill Livingstone, p. 555, ISBN 9780443071249
- McKay, Reg (19 October 2007). "Razor gangs ruled the streets but even in the violence of pre-war years, one man stood out". Daily Record. Glasgow. Retrieved 12 January 2019.